By The Associated Press and Seattle Times staff

ATLANTA — Health officials said Wednesday they are seeing more cases of a nasty skin infection caused by a common bacteria traced to the ink used for tattoos. Five confirmed cases have been reported in Washington since last fall, health officials said.

Three people were infected at a tattoo parlor in Snohomish County, including one King County resident. Two more King County residents were infected at a parlor in King County and 26 Washington residents had possible infection, according to the report by the Centers for Disease Control and Prevention (CDC).

In all cases, investigators concluded the culprit was the ink, said Michael Kinzer, an epidemic intelligence officer from the CDC working with King County's health department. The tattoo artists appeared to be meeting all the regulations, he added. There are no health regulations for the production of tattoo ink, Kinzer added.

In the largest outbreak, 19 people in Rochester, N.Y., ended up with bubbly rashes on their new tattoos, researchers reported Wednesday. In the past year, there have been 22 confirmed cases and more than 30 suspected cases of the skin infection in Colorado, Iowa, New York in addition to Washington, health officials said.

Hepatitis, staph infections and the superbug known as MRSA have been tied to tattoos.

Dirty needles and unsanitary conditions are often to blame. But all the New York cases were linked to an unidentified artist who wore disposable gloves and sterilized his instruments.

The infections were tied to ink or water used to dilute the ink. Tattoo artists and ink makers should use only sterile water to dilute ink, health officials advise.

The illnesses were caused by a bacterial cousin of tuberculosis named Mycobacterium chelonae (pronounced chell-OH-nay).

The bacteria can cause itchy and painful pus-filled blisters that can take months to clear up, and involve treatment with harsh antibiotics with unpleasant side effects.

The bacteria are common in tap water and have been seen in the past when tattoo artists used contaminated water to lighten dark ink. The ink used in New York was "gray wash," used for shaded areas of tattoos.

The ink was recalled and has not returned to the market.

"Even if you get a tattoo from a facility that does everything right, it's not risk free," said Dr. Byron Kennedy, deputy director of the health department in New York's Monroe County.

He is lead author of a report on last fall's Rochester cases that was released by The New England Journal of Medicine on Wednesday.

Some ink manufacturers add witch hazel or an alcohol preservative to lower risk of certain viruses, but those additives don't kill the hardy chelonae bacteria.

An estimated 1 in 5 U.S. adults have at least one tattoo, according to polls.